FLOW VISUALIZATION IN POROUS-MEDIA VIA POSITRON-EMISSION-TOMOGRAPHY

We demonstrate here the use of a non-invasive technique based on Posit ron Emission Tomography (PET) in visualizing and in making quantitativ e measurements of scalar transport through natural opaque permeable se diments. Along with various other possibilities, this technique has th e potential to help improve the understanding of processes that take p lace at the seabeds between the porewater and the overlying water, whi ch result in exchange of nutrients, toxins and solute. Unlike many oth er methods, PET is able to produce full three-dimensional pictures of the percolation of fluid through not only ''constructed'' but also nat ural porous media. (C) 1998 American Institute of Physics.